Question 1

Which of the following statements about spontaneous mutation is TRUE?

Accepted Answer

A)   A single mutation is common but a double mutation is very rare.
B)   If the mutation rate to antibiotic A is 10-9 per cell division, and to antibiotic B is 10-6 per cell division, the probability of the cell being resistant to both medications is 10-15.
C)   If the mutation rate to antibiotic A is 10-9 per cell division, and to antibiotic B is 10-6 per cell division, the probability of the cell being resistant to both medications is 10-54.
D)   A frameshift mutation in which three nucleotides are added is less likely to impact a cell that a frameshift mutation in which two nucleotides are deleted.
E)   A transposon may insertionally inactivate a gene when it jumps from one place in a genome to another.F) B) and E)
G) B) and C)

Question 2

Transposons may leave a cell by incorporating themselves into a plasmid.

Accepted Answer

A) True 
 B)False

Question 3

The study of the crown gall tumor found

Accepted Answer

A)   a bacterial plasmid promoter that was similar to plant promoters.
B)   an R plasmid in plant cells.
C)   incorporation of the bacterial chromosome into the plant.
D)   incorporation of the plant chromosome into the bacteria.
E)   a bacterial plasmid promoter that was similar to plant terminators.F) D) and E)
G) B) and E)

Question 4

Antibiotics

Accepted Answer

A)   cause mutations to occur.
B)   may act as alkylating mutagens.
C)   provide an environment in which preexisting mutants survive.
D)   increase the rate of spontaneous mutation.
E)   destroy all mutant bacteria.F) A) and E)
G) B) and E)

Question 5

Chemical mutagens often act by altering the

Accepted Answer

A)   alkyl groups of the nucleobase.
B)   nucleobase sequence.
C)   number of binding sites on the nucleobase.
D)   hydrogen bonding properties of the nucleobase.
E)   nucleobases.F) A) and E)
G) A) and B)

Question 6

On which of the following DNA strands would UV radiation have the most effect?

Accepted Answer

A)   AATTAGTTC
B)   AACCGGG
C)   TATATACG
D)   AUAUCGAU
E)   TATATACG AND AATTAGTTCF) B) and D)
G) None of the above

Question 7

DNA transfer by conjugation is more efficient in a liquid medium setting, subjected to very mild agitation (stirring) , rather than on an agar plate format. Why?

Accepted Answer

A)   Direct cell-to-cell contact is required for this process, and this is more likely to be achieved in the plate format than in the fluid format (especially for relatively non-motile types of bacteria) .
B)   Direct cell-to-cell contact isn't required for this process, so the ability to secrete the DNA into the surrounding fluid medium makes the process more efficient than the dry surface of an agar plate.
C)   Direct cell-to-cell contact is required for this process, and this is more likely to be achieved in the fluid liquid format than on an agar plate (especially for relatively non-motile types of bacteria) .
D)   Trick question-it can take place with the same degree of efficiency on either format. It doesn't matter!
E)   Agitation is only needed if the bacteria are known to be non-motile and can't move around on a solid medium. Otherwise, it doesn't really matter what type of medium is used as long as it contains chemicals to make cells competent.F) A) and C)
G) C) and E)

Question 8

Insertion sequences

Accepted Answer

A)   are the simplest type of transposon, code for a transposase enzyme AND can produce pili.
B)   code for a transposase enzyme AND are characterized by an inverted repeat.
C)   are characterized by an inverted repeat AND can produce pili.
D)   can produce pili AND are the simplest type of transposon.
E)   are the simplest type of transposon, code for a transposase enzyme, AND are characterized by an inverted repeat.F) A) and C)
G) B) and E)

Question 9

The mechanism by which genes are transferred into bacteria via viruses is called

Accepted Answer

A)   ellipsis.
B)   transduction.
C)   replica plating.
D)   transformation.
E)   conjugation.F) None of the above
G) B) and E)

Question 10

You explain to your patient that there has been an increase in the number of strains of S. aureus that are now resistant to methicillin. The gene conferring resistance has moved from one strain to another via mobile gene elements, an example of which is a(n)  ________.

Accepted Answer

A)   bacteriovirus
B)   insertional divider
C)   histone
D)   transposon
E)   chromosomeF) D) and E)
G) B) and D)

Question 11

Every 24 hours, every genome in every cell of the human body is damaged 10,000 times or more. Given the possible DNA repair mechanisms, which order listed below would be most effective at repairing these as quickly as possible in order to prevent mutations from being carried forward in DNA replication?

Accepted Answer

A)   Proofreading by DNA polymerase, glycosylase enzyme activities, excision repair, SOS repair
B)   SOS repair, excision repair, glycosylase enzyme activities, proofreading by DNA polymerase
C)   SOS repair, proofreading by DNA polymerase, glycosylase enzyme activities, excision repair
D)   Glycosylase enzyme activities, SOS repair, proofreading by DNA polymerase, excision repair
E)   Proofreading by DNA polymerase, SOS repair, glycosylase enzyme activities, excision repairF) B) and E)
G) A) and D)

Question 12

Thymine dimers are removed by

Accepted Answer

A)   no repair mechanisms.
B)   SOS repair AND photoreactivation repair.
C)   SOS repair AND excision repair.
D)   photoreactivation repair AND excision repair.
E)   SOS repair, photoreactivation repair AND excision repair.F) C) and E)
G) C) and D)

Question 13

Among the easiest of the mutations to isolate are those which

Accepted Answer

A)   involve polyploid chromosomes AND allow populations to be measured.
B)   involve antibiotic resistance AND allow populations to be measured.
C)   allow populations to be measured AND use an indirect method for measurement.
D)   involve haploid chromosomes AND involve antibiotic resistance.
E)   use an indirect method for measurement AND involve antibiotic resistance.F) A) and B)
G) A) and E)

Question 14

Organisms termed his- are considered prototrophic for histidine.

Accepted Answer

A) True 
 B)False

Question 15

Which of the following statements is CORRECT regarding transformation?

Accepted Answer

A)   DNA is transferred from one bacterial cell to another by means of a bacteriophage.
B)   Transformation is the uptake of "naked" DNA from the environment.
C)   Transformation involves the formation of a sex pilus through which plasmid DNA is shared between bacteria.
D)   Transformation depends on a donor cell containing an F plasmid and a recipient cell that does not.
E)   Transformation is a process that depends on physical contact between two bacterial cells.F) B) and C)
G) A) and B)

Question 16

To increase the proportion of auxotrophic mutants in a population of bacteria, one may use

Accepted Answer

A)   direct selection.
B)   replica plating.
C)   penicillin enrichment.
D)   individual transfer.
E)   mutant reversion.F) C) and D)
G) A) and E)

Question 17

Which is NOT true about mismatch repair?

Accepted Answer

A)   It uses an endonuclease.
B)   It requires DNA polymerase and DNA ligase.
C)   It uses methylation of the DNA to differentiate between strands.
D)   It removes both strands in the mismatch area.
E)   It fixes errors missed by the proofreading of DNA polymerase.F) A) and B)
G) C) and D)

Question 18

What concerns you most about the strain of H. influenzae that you may be exposed to while you are away is antibiotic resistance. The genes for resistance can be acquired by this organism as naked DNA from the environment, an example of

Accepted Answer

A)   conjugation.
B)   transformation.
C)   induced mutation.
D)   vertical gene transfer.
E)   transduction.F) A) and E)
G) B) and E)

Question 19

Strong chemical mutagens may be used to treat cancer cells. Is this a good or bad idea?

Accepted Answer

A)   Good-kill those cancer cells as quickly as possible to cure the patient!
B)   Bad-these mutagens will also affect the non-cancerous cells, possibly leading to new cancerous states!
C)   Good and bad-they're very good at killing cancer cells, but they could also be dangerous to non-cancerous cells.
D)   Bad-the cancer cells are already mutated. We don't want to mutate them more and make them more cancerous!
E)   Bad-the medications are toxic and will cause healthy normal microbiots to become cancerous.F) A) and B)
G) D) and E)

Question 20

Bacteria that have properties of both the donor and recipient cells are the result of

Accepted Answer

A)   UV light.
B)   SOS repair.
C)   frame shift mutations.
D)   genetic recombination.
E)   antibiotic resistance.F) B) and C)
G) All of the above

Exam 8: Bacterial Genetics

What concerns you most about the strain of H. influenzae that you may be exposed to while you are away is antibiotic resistance. The genes for resistance can be acquired by this organism as naked DNA from the environment, an example of

Correct Answer
verified

Chemical mutagens often act by altering the

Correct Answer
verified

On which of the following DNA strands would UV radiation have the most effect?

Correct Answer
verified

Antibiotics

Correct Answer
verified

Strong chemical mutagens may be used to treat cancer cells. Is this a good or bad idea?

Correct Answer
verified

To increase the proportion of auxotrophic mutants in a population of bacteria, one may use

Correct Answer
verified

Transposons may leave a cell by incorporating themselves into a plasmid.

Correct Answer
verified

You explain to your patient that there has been an increase in the number of strains of S. aureus that are now resistant to methicillin. The gene conferring resistance has moved from one strain to another via mobile gene elements, an example of which is a(n) ________.

Correct Answer
verified

Bacteria that have properties of both the donor and recipient cells are the result of

Correct Answer
verified

Thymine dimers are removed by

Correct Answer
verified

Which of the following statements about spontaneous mutation is TRUE?

Correct Answer
verified

Insertion sequences

Correct Answer
verified

Which of the following statements is CORRECT regarding transformation?

Correct Answer
verified

Which is NOT true about mismatch repair?

Correct Answer
verified

Organisms termed his- are considered prototrophic for histidine.

Correct Answer
verified

DNA transfer by conjugation is more efficient in a liquid medium setting, subjected to very mild agitation (stirring) , rather than on an agar plate format. Why?

Correct Answer
verified

The study of the crown gall tumor found

Correct Answer
verified

The mechanism by which genes are transferred into bacteria via viruses is called

Correct Answer
verified

Correct Answer
verified

Among the easiest of the mutations to isolate are those which

Correct Answer
verified

Exam 8: Bacterial Genetics

What concerns you most about the strain of H. influenzae that you may be exposed to while you are away is antibiotic resistance. The genes for resistance can be acquired by this organism as naked DNA from the environment, an example of

Correct AnswerverifiedShow Answer

Chemical mutagens often act by altering the

Correct AnswerverifiedShow Answer

On which of the following DNA strands would UV radiation have the most effect?

Correct AnswerverifiedShow Answer

Antibiotics

Correct AnswerverifiedShow Answer

Strong chemical mutagens may be used to treat cancer cells. Is this a good or bad idea?

Correct AnswerverifiedShow Answer

To increase the proportion of auxotrophic mutants in a population of bacteria, one may use

Correct AnswerverifiedShow Answer

Transposons may leave a cell by incorporating themselves into a plasmid.

Correct AnswerverifiedShow Answer

You explain to your patient that there has been an increase in the number of strains of S. aureus that are now resistant to methicillin. The gene conferring resistance has moved from one strain to another via mobile gene elements, an example of which is a(n) ________.

Correct AnswerverifiedShow Answer

Bacteria that have properties of both the donor and recipient cells are the result of

Correct AnswerverifiedShow Answer

Thymine dimers are removed by

Correct AnswerverifiedShow Answer

Which of the following statements about spontaneous mutation is TRUE?

Correct AnswerverifiedShow Answer

Insertion sequences

Correct AnswerverifiedShow Answer

Which of the following statements is CORRECT regarding transformation?

Correct AnswerverifiedShow Answer

Which is NOT true about mismatch repair?

Correct AnswerverifiedShow Answer

Organisms termed his- are considered prototrophic for histidine.

Correct AnswerverifiedShow Answer

DNA transfer by conjugation is more efficient in a liquid medium setting, subjected to very mild agitation (stirring) , rather than on an agar plate format. Why?

Correct AnswerverifiedShow Answer

The study of the crown gall tumor found

Correct AnswerverifiedShow Answer

The mechanism by which genes are transferred into bacteria via viruses is called

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

Among the easiest of the mutations to isolate are those which

Correct AnswerverifiedShow Answer

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